Vale opening and closing time detecting apparatus and method thereof for electromagnetically operated valve mechanism in internal combustion engine

Abstract

A valve opening and closing time detecting apparatus and method of an elecromagnetically operated valve in an internal combustion engine comprises a vibration detecting means for detecting a vibration generated when the valve reaches a fully open position or when the valve reaches a valve seated position and a judging means for comparing a comparison data obtained from the vibration detecting means with a threshold value and for judging that the valve has reached the open position or the seated position when the comparison data exceeds the threshold value.

What is claimed is:  
     
       1. A valve opening and closing time detecting apparatus for an electromagnetically operated valve ( 1 ) provided on a cylinder head ( 2 ) of an internal combustion engine having: a valve body ( 4 ) inserted in said cylinder head ( 2 ) for closing a port provided therein by tightly seating a valve head ( 4   a ) of said valve body ( 4 ) on a valve seat ( 12 ) and for opening said port by keeping said valve head ( 4   a ) away from said valve seat ( 12 ), an armature ( 17 ) provided on said valve head ( 4   a ) in a lift adjuster ( 8 ), a first coil ( 5 ) provided to surround a stem ( 4   b ) of said valve body ( 4 ) for opening said port by drawing said armature ( 17 ) against a closing force of a first spring ( 13 ), a second coil ( 6 ) provided on said armature ( 17 ) for closing said port by drawing thereof against an opening force of a second spring ( 19 ), and a crank angle sensor ( 21 ) for detecting a number of crank-shaft revolutions of said engine and for producing an r.p.m. signal, comprising: 
       a vibration sensor ( 20 ) directly attached to said cylinder head ( 2 ) proximate to said first coil ( 5 ) for receiving only a vibration of said valve body ( 4 ) when said valve head ( 4   a ) contacts upon said valve seat ( 12 ), and reaches a maximum lifted position from said valve seat ( 12 ) while said engine is operating and for generating a vibration signal;  
       trigger signal generating means ( 31 ) responsive to said r.p.m. signal and said vibration signal for storing threshold values of vibrations corresponding to each r.p.m. and for producing a trigger signal; and  
       judging means ( 30 ) responsive to said vibration signal and said trigger signal for deciding exact closing and opening times of said valve ( 1 ) by comparing said vibration signal with said threshold values corresponding to a present r.p.m. so as to avoid receiving noises due to aging and manufacturing allowances of said valve ( 1 ) by an installation of said vibration sensor ( 20 ) in immediate vicinity of said valve.  
     
     
       2. The valve opening and closing time detecting apparatus according to claim  1 , wherein; 
       said threshold value is a predetermined fixed value at any engine r.p.m.  
     
     
       3. The valve opening and closing time detecting apparatus according to claim  1 , wherein: 
       said threshold value is variable in accordance with a magnitude of said vibration signal.  
     
     
       4. The valve opening and closing time detecting apparatus according to claim  3 , wherein: 
       said threshold value can be updated at any engine r.p.m.  
     
     
       5. The valve opening and closing time detecting apparatus according to claim  3 , wherein: 
       said magnitude is a peak value of said vibration signal.  
     
     
       6. The valve opening and closing time detecting apparatus according to claim  3 , wherein: 
       said magnitude is a mean value of said vibration signal when said valve is between a maximum lifted position and a valve seat position.  
     
     
       7. A valve opening and closing time detecting apparatus for an electromagnetically operated valve ( 1 ) provided on a cylinder head ( 2 ) of an internal combustion engine having: a valve body ( 4 ) inserted in said cylinder head ( 2 ) for closing a port provided therein by tightly seating a valve head ( 4   a ) of said valve body ( 4 ) on a valve seat ( 12 ), and for opening said port by keeping said valve head ( 4   a ) away from said valve seat ( 12 ), an armature ( 17 ) provided on said valve head ( 4   a ) in a lift adjuster ( 8 ), a first coil ( 5 ) provided to surround a stem ( 4   b ) of said valve body ( 4 ) for opening said port by drawing said armature ( 17 ) against a closing force of a first spring ( 13 ), a second coil ( 6 ) provided on said armature ( 17 ) for closing said port by drawing thereof against an opening force of a second spring ( 19 ), and a crank angle sensor ( 21 ) for detecting a number of crank-shaft revolutions of said engine and for producing an r.p.m. signal, comprising: 
       a vibration sensor ( 20 ) directly attached to said cylinder head ( 2 ) in proximity to said first coil ( 5 ) for receiving only a vibration of said valve body ( 4 ) when said valve head ( 4   a ) contacts upon said valve seat ( 12 ), and reaches a maximum lifted position from said valve seat ( 12 ) while said engine is operating and for generating a vibration signal;  
       trigger signal generating means ( 31 ) responsive to said r.p.m. signal and said vibration signal for storing threshold values of vibrations corresponding to each engine revolution, and for producing a trigger signal; and  
       judging means ( 30 ) responsive to said vibration signal and said trigger signal for deciding exact closing and opening times of said valve ( 1 ) when said vibration signal becomes far larger than a predetermined threshold frequency value corresponding to a present r.p.m. so as to avoid receiving noises due to aging and manufacturing allowances of said valve ( 1 ) by a close installation of said vibration sensor ( 20 ) in immediate vicinity thereof.  
     
     
       8. A valve opening and closing time detecting apparatus for an electromagnetically operated valve ( 1 ) provided on a cylinder head ( 2 ) of an internal combustion engine having: a valve body ( 4 ) inserted in said cylinder head ( 2 ) for closing a port provided therein by tightly seating a valve head ( 4   a ) of said valve body ( 4 ) on a valve seat ( 12 ), and for opening said port by keeping said valve head ( 4   a ) away from said valve seat ( 12 ), an armature ( 17 ) provided on said valve head ( 4   a ) in a lift adjuster ( 8 ), a first coil ( 5 ) provided to surround a stem ( 4   b ) of said valve body ( 4 ) for opening said port by drawing said armature ( 17 ) against a closing force of a first spring ( 13 ), a second coil ( 6 ) provided on said armature ( 17 ) for closing said port by drawing thereof against an opening force of a second spring ( 19 ), and a crank angle sensor ( 21 ) for detecting a number of crank-shaft revolutions of said engine and for producing an r.p.m. signal, comprising: 
       a vibration sensor ( 20 ) directly attached to said cylinder head ( 2 ) in proximity to said first coil ( 5 ) for receiving only a vibration of said valve body ( 4 ) when said valve head ( 4   a ) contacts upon said valve seat ( 12 ), and reaches a maximum lifted position from said valve seat ( 12 ) while said engine is operating and for generating a vibration signal;  
       trigger signal generating means ( 31 ) responsive to said r.p.m. signal and said vibration signal for storing threshold values of vibrations corresponding to each engine revolution and for producing a trigger signal; and  
       judging means ( 30 ) responsive to said vibration signal and said trigger signal for deciding exact closing and opening times of said valve ( 1 ) when said vibration signal consequently exceeds one of said threshold values, for more than a predetermined time period, so as to avoid receiving noises due to aging and manufacturing allowances of said valve ( 1 ) by installation of said vibration sensor ( 20 ) in immediate vicinity of said valve.  
     
     
       9. A valve opening and closing time detection method for an electromagnetically operated valve ( 1 ) provided on a cylinder head ( 2 ) of an internal combustion engine having: a valve body ( 4 ) inserted in said cylinder head ( 2 ) for closing a port provided therein by tightly seating a valve head ( 4   a ) of said valve body ( 4 ) on a valve seat ( 12 ), and for opening said port by keeping said valve head ( 4   a ) away from said valve seat ( 12 ), an armature ( 17 ) provided on said valve head ( 4   a ) in a lift adjuster ( 8 ), a first coil ( 5 ) provided to surround a stem ( 4   b ) of said valve body ( 4 ) for opening said port by drawing said armature ( 17 ) against a closing force of a first spring ( 13 ), a second coil ( 6 ) provided on said armature ( 17 ) for closing said port by drawing thereof against an opening force of a second spring ( 19 ), and a crank angle sensor ( 21 ) for detecting a number of crank-shaft revolutions of said engine, comprising the steps of: 
       providing a vibration sensor ( 20 ) directly to said cylinder head ( 2 ) in proximity to said first coil ( 5 );  
       receiving only a vibration of said valve body ( 4 ) when said valve head ( 4   a ) contacts upon said valve seat ( 12 ), and reaches a maximum lifted position from said valve seat ( 12 ) while said engine is operating;  
       storing threshold values of vibrations corresponding to each engine revolution; and  
       deciding exact closing and opening times of said valve ( 1 ) when said vibration becomes larger than said threshold value so as to avoid receiving noises due to aging and manufacturing allowances of said valve ( 1 ) by installing said vibration sensor ( 20 ) in proximity of said valve ( 1 ) on said cylinder head.  
     
     
       10. A valve opening and closing time detecting method for an electromagnetically operated valve ( 1 ) provided on a cylinder head ( 2 ) of an internal combustion engine having: a valve body ( 4 ) inserted in said cylinder head ( 2 ) for closing a port provided therein by tightly seating a valve head ( 4   a ) of said valve body ( 4 ) on a valve seat ( 12 ), and for opening said port by keeping said valve head ( 4   a ) away from said valve seat ( 12 ), an armature ( 17 ) provided on said valve head ( 4   a ) in a lift adjuster ( 8 ), a first coil ( 5 ) provided to surround a stem ( 4   b ) of said valve body ( 4 ) for opening said port by drawing said armature ( 17 ) against a closing force of a first spring ( 13 ), a second coil ( 6 ) provided on said armature ( 17 ) for closing said port by drawing thereof against an opening force of a second spring ( 19 ), and a crank angle sensor ( 21 ) for detecting a number of crank-shaft revolutions of said engine, comprising the steps of: 
       providing a vibration sensor ( 20 ) directly to said cylinder head ( 2 ) in proximity to said first coil ( 5 );  
       receiving only a vibration of said valve body ( 4 ) when said valve head ( 4   a ) contacts upon said valve seat ( 12 ), and reaches a maximum lifted position from said valve seat ( 12 ) while said engine is operating;  
       storing threshold values of vibrations corresponding to each engine revolution; and  
       deciding exact closing and opening times of said valve ( 1 ) when said vibration becomes larger than a predetermined frequency value so as to avoid receiving noises due to aging and manufacturing allowances of said valve ( 1 ) by installing said vibration sensor ( 20 ) in proximity to said valve ( 1 ) on said cylinder head.  
     
     
       11. A valve opening and closing time detecting method for an electromagnetically operated valve ( 1 ) provided on a cylinder head ( 2 ) of an internal combustion engine having: a valve body ( 4 ) inserted in said cylinder head ( 2 ) for closing a port provided therein by tightly seating a valve head ( 4   a ) of said valve body ( 4 ) on a valve seat ( 12 ), and for opening said port by keeping said valve head ( 4   a ) away from said valve seat ( 12 ), an armature ( 17 ) provided on said valve head ( 4   a ) in a lift adjuster ( 8 ), a first coil ( 5 ) provided to surround a stem ( 4   b ) of said valve body ( 4 ) for opening said port by drawing said armature ( 17 ) against a closing force of a first spring ( 13 ), a second coil ( 6 ) provided on said armature ( 17 ) for closing said port by drawing thereof against an opening force of a second spring ( 19 ), and a crank angle sensor ( 21 ) for detecting a number of crank-shaft revolutions of said engine, comprising the steps of: 
       providing a vibration sensor ( 20 ) directly to said cylinder head ( 2 ) at a very close position to said first coil ( 5 );  
       receiving only a vibration of said valve body ( 4 ) when said valve head ( 4   a ) contacts upon said valve seat ( 12 ), and reaches a maximum lifted position from said valve seat ( 12 ) while said engine is operating;  
       storing threshold values of vibrations corresponding to each engine revolution; and  
       deciding exact closing and opening times of said valve ( 1 ) when said vibration becomes larger than one of said threshold values for more than a predetermined time period so as to avoid receiving noises due to aging and manufacturing allowances of said valve ( 1 ) by installing said vibration sensor ( 20 ) in proximity of said valve ( 1 ) on said cylinder head.